Butterflies of the
Common Grass Yellow
Family - PIERIDAE
subfamily - COLIADINAE
© Adrian Hoskins
The Grass Yellows
are all fairly small butterflies, readily recognised by their bright
yellow wings and their habit of gathering in small groups on patches
of damp sand or soil. Despite their name, none of their caterpillars
feed on grasses - the name is derived from the fact that most
species are found in disturbed grassy habitats.
Grass Yellows are among the most familiar of tropical butterflies,
with a total of 70 known species worldwide, of which 36 are found in
the Neotropical region, 13 in North America ( including Mexico ), 10
in Africa, 25 in the Oriental region and 10 in Australia / Papua New
Guinea. Many of the species are migratory in behaviour, with the
ranges of several such as hecabe
overlapping into in 2 or more of the zoogeographical regions.
Eurema hecabe is found across the
entire African continent, throughout most of Asia south of the
Himalayas, on most of the islands of the south Pacific, and across
much of Australia.
species is found in secondary or disturbed habitats including forest
clearings, along roadsides and riverbanks, and in parks and gardens
at elevations between sea level and about 1500 metres.
The eggs of
Eurema species are always
spindle-shaped, and pale yellow or straw coloured when first laid,
changing to a darker shade before hatching. They are laid singly on
the upperside of leaves of the foodplants.
The foodplants of
hecabe vary according to the region and
habitat. They include Caesalpinia and
Cassia, ( Caesalpiniaceae ),
Pithecellobium ( Mimosaceae ) and
Wagatea ( Fabaceae ).
when first hatched is green, cylindrical, and covered in tiny
tubercules from each of which arises a single long stiff hair. In
later instars the hairs ( setae ) become progressively shorter. The
fully grown larva is dull green with a thin dark dorsal stripe, and
a broader cream lateral stripe below the spiracles. Each segment of
the body is ribbed vertically, and covered in small tubercules,
giving it a rough textured appearance.
The pale green
chrysalis is slim, sharply pointed at head and tail, and with
prominent wing cases.
Males congregate to
imbibe mineralised moisture from damp sandbanks, often in scores.
Females are more discreet in behaviour, normally being seen singly
when nectaring. They will visit many different flowers including
Lantana and various Asteraceae. Both
sexes roost overnight and during overcast weather under the leaves
of bushes or low herbage.